Amount, after tax, of accumulated gain (loss) on derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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Nominal or face amount used to calculate payments on the derivative asset.

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The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

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Derivative Instruments and Hedging Activities - Additional Information (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019 USD ($) swap	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) swap	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Derivative [Line Items]
Number of credit swaps \| swap	19		19
Derivative instrument not designated as hedging instruments, liability	$ 10.4		$ 10.4
Aggregate fair value of net liability position	24.3		24.3
Interest rate swaps
Derivative [Line Items]
Accumulated net after-tax losses related to effective cash flow hedges	4.2		4.2		$ 4.0
Estimated amount of interest rate derivatives to be reclassified to interest expense			2.7
Fair value hedge \| Noninterest Income \| Interest rate swaps
Derivative [Line Items]
Fee income related to derivative interest rate swaps executed with commercial loan customers	13.9	$ 4.0	23.4	$ 11.7
Derivatives not designated as hedging instruments
Derivative [Line Items]
Aggregate notional amount of derivative asset	$ 110.9		$ 110.9